Conventional computer disk drivers on IBM compatible personal computers (PCs) such as those from Compaq, Hewlett Packard, Texas Instruments and even Apple generally use a standard 31/2 inch floppy diskette cartridges. It has become a wide practice for persons to manually pass these floppy diskettes around when updating and submitting papers to other parties. Typically, the only way of protecting a single 31/2 inch floppy diskette cartridges is to use the paper type sleeve they come in. However, there are problems with being able to manually transport individual diskette cartridges. The paper sleeves are usually paper-thin, easily wear and become torn after a short use. Additionally, the size of these floppy diskette cartridges makes them difficult to attach to hardcopy paper versions with traditional fastening means such as paper clips. The large size of these catridges can cause the cartridge to become separated from the attached paper and become lost. Furthermore, the bulky 31/2 inch rigid square shape of the cartridge requires a storage space of at least those dimensions. The large plastic carrying cases which hold multiple disks are too cumbersome to be used for holding just a single disk. Most 31/2 inch floppy diskettes that pass around offices utilize less than 20 to 30% of their storage space resulting in substantial wasted space. Furthermore most 31/2 inch diskettes are not passed around in protective paper type sleeves, and as a result the magnetic disk in the diskette cartridges can become demagnetized and even damaged form normal wear and tear.
Cartridge and disk adapters have been proposed over the past several years, but fail to overcome all the problems described above. U.S. Pat. No. 5,208,802 to Suzuki et al. describes a disk adapter for a disk cartridge that uses a spacer-component to fill in the space about smaller sized disks. However, Suzuki '802 requires using a separate plastic disk adapter piece as the spacer-component that detaches from the cartridge housing and thus can become easily damaged, and lost. Furthermore, both this plastic adapter piece and the disk must each be inserted and snapped into place within the housing between uses which would tend to wear out the plastic adapter over time and thus not allow it to be readily reusable. U.S. Pat. No. 5,150,354 to Iwata et al. describes a disk cartridge having a hinged side opening for allowing only a full size magnetic disk to be inserted therein. U.S. Pat. No. 5,475,674 to Yamashita et al. describes a disc case that is limited to only holding full-sized removable magnetic disks. U.S. Pat. Nos. 5,331,627 to Childers et al.; 5,677,898 to Hasegawa et al. and 5,715,233 to Yoshida et al. each describes cartridge adapter devices where one or more smaller cartridges (each housing a disk) can be inserted into a larger cartridge so that the smaller cartridge can work in computers that take the larger cartridges.